Use safeDel in after hook

Author: angelapwen

extensions/ql-vscode/src/vscode-tests/no-workspace/query-results.test.ts

@@ -179,6 +179,7 @@ describe('query-results', () => {
 
     afterEach(async () => {
       sandbox.restore();
+      safeDel(interpretedResultsPath);
     });
 
     it('should interpretResultsSarif', async function() {
@@ -430,6 +431,14 @@ describe('query-results', () => {
     });
   });
 
+  function safeDel(file: string) {
+    try {
+      fs.unlinkSync(file);
+    } catch (e) {
+      // ignore
+    }
+  }
+
   function createMockQueryWithResults(
     queryPath: string,
     didRunSuccessfully = true,